A chemical, biological, radiological, or nuclear (CBRN) attack on a civilian population is a dreadful event. The best response requires the earliest possible detection of the attack so that individuals can flee and civil defense authorities can contain its effects. To this end, chemical, biological, radiological, and nuclear (CBRN) attack-detection systems are being deployed in many urban centers.
It is important, of course, that a CBRN attack-detection system is able to quickly determine that an attack has occurred. But it is also important that the attack-detection system does not issue false alarms. As a consequence, testing and calibration of each attack-detection system is important.
It would be desirable to test and calibrate each CBRN attack-detection system at its intended deployment location. But to do so would be very expensive and, of course, only simulants, not the actual agents of interest, could be used. The current practice for testing and calibration is to release physical simulants in outdoor test locations or in special test chambers. This approach is of questionable value and relatively expensive.
First, to the extent that the calibration is performed outdoors, simulants, rather than the actual agents (e.g., anthrax, etc.) must be used. Second, due to the aforementioned expense of repeated runs, attack-detection systems are typically calibrated based on only a limited number of attack scenarios. This brings into question the ability of the detector to accurately discriminate over a wide range of scenarios. Third, whether the calibration is performed outdoors or in a special test chamber, it doesn't replicate the actual environment in which the system is to operate. Differences in terrain and ambient conditions between the test site and the actual deployment location will affect the accuracy of the calibration.
Regarding expense, every system that is scheduled to be deployed must be tested. Furthermore, a large number of attack scenarios (e.g., different concentrations, different simulants, etc.) should be simulated for proper calibration. Each additional run means added expense.
In view of present practice, and the implications of inaccuracy, there is a need for a more reliable, accurate, and cost-effective approach for testing and calibrating attack-detection systems.